Total knee replacement arthroplasty (TKRA) in severe osteoarthritis usually requires extensive soft tissue and bone dissection associated with substantial bleeding. Because TKRA is performed with a pneumatic tourniquet, intraoperative bleeding is not substantial, however, over 80% of the total blood loss occurs within the first 24 hour after the operation and the hidden blood loss is 50% of the total loss, making the true blood loss twice. Consequently, many patients can become anemic at early postoperative period and this anemic condition may lead to overall physical deterioration which include fatigue, dizziness, reduced exercise tolerance and delayed recovery.